Concentration profile calculation for buried ion-exchanged channel waveguides in glass using explicit space-charge analysis

Ionic conductivity inhomogeneity and its relation to space charge is analyz ed in the case of a two-ion exchange for channel waveguide fabrication in o ptical glass, The space-charge evolution equation is derived and discussed in a general binary ion exchange context, This leads to an efficient algori thm which computes current-density nonuniformity in the field-assisted bury ing of ion-exchanged waveguides, The algorithm exhibits excellent agreement with the classic potential equation perturbed by nonhomogeneous ionic cond uctivity, and is appreciably faster, We show that the homogeneous current-d ensity assumption is inaccurate for the calculation of the burying depth an d waveguide size in the case of a realistic glass with nonlinear ionic diff usivity.